From c79706ff4ce591df2151db5504d3c224f3c9965f Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Mon, 27 Feb 2017 13:17:51 +0000 Subject: ext: Add pybind rev f4b81b3 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Change-Id: I52e4fc9ebf2f59da57d8cf8f3e37cc79598c2f5f Signed-off-by: Andreas Sandberg Reviewed-by: Andreas Hansson Reviewed-by: Curtis Dunham Reviewed-on: https://gem5-review.googlesource.com/2229 Reviewed-by: Tony Gutierrez Reviewed-by: Jason Lowe-Power Reviewed-by: Pierre-Yves Péneau --- ext/pybind11/tests/constructor_stats.h | 249 +++++++++++++++++++++++++++++++++ 1 file changed, 249 insertions(+) create mode 100644 ext/pybind11/tests/constructor_stats.h (limited to 'ext/pybind11/tests/constructor_stats.h') diff --git a/ext/pybind11/tests/constructor_stats.h b/ext/pybind11/tests/constructor_stats.h new file mode 100644 index 000000000..eb3e49cab --- /dev/null +++ b/ext/pybind11/tests/constructor_stats.h @@ -0,0 +1,249 @@ +#pragma once +/* + tests/constructor_stats.h -- framework for printing and tracking object + instance lifetimes in example/test code. + + Copyright (c) 2016 Jason Rhinelander + + All rights reserved. Use of this source code is governed by a + BSD-style license that can be found in the LICENSE file. + +This header provides a few useful tools for writing examples or tests that want to check and/or +display object instance lifetimes. It requires that you include this header and add the following +function calls to constructors: + + class MyClass { + MyClass() { ...; print_default_created(this); } + ~MyClass() { ...; print_destroyed(this); } + MyClass(const MyClass &c) { ...; print_copy_created(this); } + MyClass(MyClass &&c) { ...; print_move_created(this); } + MyClass(int a, int b) { ...; print_created(this, a, b); } + MyClass &operator=(const MyClass &c) { ...; print_copy_assigned(this); } + MyClass &operator=(MyClass &&c) { ...; print_move_assigned(this); } + + ... + } + +You can find various examples of these in several of the existing example .cpp files. (Of course +you don't need to add any of the above constructors/operators that you don't actually have, except +for the destructor). + +Each of these will print an appropriate message such as: + + ### MyClass @ 0x2801910 created via default constructor + ### MyClass @ 0x27fa780 created 100 200 + ### MyClass @ 0x2801910 destroyed + ### MyClass @ 0x27fa780 destroyed + +You can also include extra arguments (such as the 100, 200 in the output above, coming from the +value constructor) for all of the above methods which will be included in the output. + +For testing, each of these also keeps track the created instances and allows you to check how many +of the various constructors have been invoked from the Python side via code such as: + + from example import ConstructorStats + cstats = ConstructorStats.get(MyClass) + print(cstats.alive()) + print(cstats.default_constructions) + +Note that `.alive()` should usually be the first thing you call as it invokes Python's garbage +collector to actually destroy objects that aren't yet referenced. + +For everything except copy and move constructors and destructors, any extra values given to the +print_...() function is stored in a class-specific values list which you can retrieve and inspect +from the ConstructorStats instance `.values()` method. + +In some cases, when you need to track instances of a C++ class not registered with pybind11, you +need to add a function returning the ConstructorStats for the C++ class; this can be done with: + + m.def("get_special_cstats", &ConstructorStats::get, py::return_value_policy::reference) + +Finally, you can suppress the output messages, but keep the constructor tracking (for +inspection/testing in python) by using the functions with `print_` replaced with `track_` (e.g. +`track_copy_created(this)`). + +*/ + +#include "pybind11_tests.h" +#include +#include +#include +#include + +class ConstructorStats { +protected: + std::unordered_map _instances; // Need a map rather than set because members can shared address with parents + std::list _values; // Used to track values (e.g. of value constructors) +public: + int default_constructions = 0; + int copy_constructions = 0; + int move_constructions = 0; + int copy_assignments = 0; + int move_assignments = 0; + + void copy_created(void *inst) { + created(inst); + copy_constructions++; + } + void move_created(void *inst) { + created(inst); + move_constructions++; + } + void default_created(void *inst) { + created(inst); + default_constructions++; + } + void created(void *inst) { + ++_instances[inst]; + }; + void destroyed(void *inst) { + if (--_instances[inst] < 0) + throw std::runtime_error("cstats.destroyed() called with unknown instance; potential double-destruction or a missing cstats.created()"); + } + + int alive() { + // Force garbage collection to ensure any pending destructors are invoked: + py::module::import("gc").attr("collect")(); + int total = 0; + for (const auto &p : _instances) if (p.second > 0) total += p.second; + return total; + } + + void value() {} // Recursion terminator + // Takes one or more values, converts them to strings, then stores them. + template void value(const T &v, Tmore &&...args) { + std::ostringstream oss; + oss << v; + _values.push_back(oss.str()); + value(std::forward(args)...); + } + + // Move out stored values + py::list values() { + py::list l; + for (const auto &v : _values) l.append(py::cast(v)); + _values.clear(); + return l; + } + + // Gets constructor stats from a C++ type index + static ConstructorStats& get(std::type_index type) { + static std::unordered_map all_cstats; + return all_cstats[type]; + } + + // Gets constructor stats from a C++ type + template static ConstructorStats& get() { + return get(typeid(T)); + } + + // Gets constructor stats from a Python class + static ConstructorStats& get(py::object class_) { + auto &internals = py::detail::get_internals(); + const std::type_index *t1 = nullptr, *t2 = nullptr; + try { + auto *type_info = internals.registered_types_py.at(class_.ptr()); + for (auto &p : internals.registered_types_cpp) { + if (p.second == type_info) { + if (t1) { + t2 = &p.first; + break; + } + t1 = &p.first; + } + } + } + catch (std::out_of_range) {} + if (!t1) throw std::runtime_error("Unknown class passed to ConstructorStats::get()"); + auto &cs1 = get(*t1); + // If we have both a t1 and t2 match, one is probably the trampoline class; return whichever + // has more constructions (typically one or the other will be 0) + if (t2) { + auto &cs2 = get(*t2); + int cs1_total = cs1.default_constructions + cs1.copy_constructions + cs1.move_constructions + (int) cs1._values.size(); + int cs2_total = cs2.default_constructions + cs2.copy_constructions + cs2.move_constructions + (int) cs2._values.size(); + if (cs2_total > cs1_total) return cs2; + } + return cs1; + } +}; + +// To track construction/destruction, you need to call these methods from the various +// constructors/operators. The ones that take extra values record the given values in the +// constructor stats values for later inspection. +template void track_copy_created(T *inst) { ConstructorStats::get().copy_created(inst); } +template void track_move_created(T *inst) { ConstructorStats::get().move_created(inst); } +template void track_copy_assigned(T *, Values &&...values) { + auto &cst = ConstructorStats::get(); + cst.copy_assignments++; + cst.value(std::forward(values)...); +} +template void track_move_assigned(T *, Values &&...values) { + auto &cst = ConstructorStats::get(); + cst.move_assignments++; + cst.value(std::forward(values)...); +} +template void track_default_created(T *inst, Values &&...values) { + auto &cst = ConstructorStats::get(); + cst.default_created(inst); + cst.value(std::forward(values)...); +} +template void track_created(T *inst, Values &&...values) { + auto &cst = ConstructorStats::get(); + cst.created(inst); + cst.value(std::forward(values)...); +} +template void track_destroyed(T *inst) { + ConstructorStats::get().destroyed(inst); +} +template void track_values(T *, Values &&...values) { + ConstructorStats::get().value(std::forward(values)...); +} + +/// Don't cast pointers to Python, print them as strings +inline const char *format_ptrs(const char *p) { return p; } +template +py::str format_ptrs(T *p) { return "{:#x}"_s.format(reinterpret_cast(p)); } +template +auto format_ptrs(T &&x) -> decltype(std::forward(x)) { return std::forward(x); } + +template +void print_constr_details(T *inst, const std::string &action, Output &&...output) { + py::print("###", py::type_id(), "@", format_ptrs(inst), action, + format_ptrs(std::forward(output))...); +} + +// Verbose versions of the above: +template void print_copy_created(T *inst, Values &&...values) { // NB: this prints, but doesn't store, given values + print_constr_details(inst, "created via copy constructor", values...); + track_copy_created(inst); +} +template void print_move_created(T *inst, Values &&...values) { // NB: this prints, but doesn't store, given values + print_constr_details(inst, "created via move constructor", values...); + track_move_created(inst); +} +template void print_copy_assigned(T *inst, Values &&...values) { + print_constr_details(inst, "assigned via copy assignment", values...); + track_copy_assigned(inst, values...); +} +template void print_move_assigned(T *inst, Values &&...values) { + print_constr_details(inst, "assigned via move assignment", values...); + track_move_assigned(inst, values...); +} +template void print_default_created(T *inst, Values &&...values) { + print_constr_details(inst, "created via default constructor", values...); + track_default_created(inst, values...); +} +template void print_created(T *inst, Values &&...values) { + print_constr_details(inst, "created", values...); + track_created(inst, values...); +} +template void print_destroyed(T *inst, Values &&...values) { // Prints but doesn't store given values + print_constr_details(inst, "destroyed", values...); + track_destroyed(inst); +} +template void print_values(T *inst, Values &&...values) { + print_constr_details(inst, ":", values...); + track_values(inst, values...); +} + -- cgit v1.2.3